zinc oxide (zno) nanoparticles were synthesized by spray pyrolysis method using an aqueous solution of zinc acetate at various concentrations from 5 to 25 wt%. the decomposition of precursor solutions was carried out at 800, 1000 and 1200ºc under different atomizing pressures. the crystal structure and morphology of synthesized nanoparticles were characterized by x-ray diffraction (xrd) spectro...

since heavy metals are considered as one of the major pollutants threatening, the main goal of this study was to bring out the concentrations of pb, zn and mn in the surface sediments off bushehr in the persian gulf. for this purpose, after collection of samples, the concentrations of the three metals in surface sediments were measured through the atomic absorption. the results were compared wi...

Well faceted CuO nanoparticles, were synthesized by thermal-assisted dissociation method at reflux temperature in a short period of time. A possible mechanism for synthesis of such highly pure and stable nanoparticles is tentatively proposed by FT-IR study. The large surface area and rich exposed active sites are expected to endow such nanoparticles with excellent performances in catalysis as d...

abstract phosphate is an essential element for plants, animals, and human. mobility and availability of phosphate in the natural systems is controlled by the adsorption-desorption and dissolution-precipitation reactions. iron (hydr)oxides including goethite play an important role in phosphate adsorption reactions in soil. surface area, crystallinity, and morphology of iron (hydr)oxides are the ...

The cell surface areas of 3T3 and SV40-3T3 cells both for suspended and for flat cells growing on the culture substrate have been determined in dependence on growth density. The surface areas of flat 3T3 and SV40-3T3 cells turn out to be independent of growth density over a wide range. For 3T3 cells the surface area of flat cells compares well with that determined by Collard and Temmink for sus...

We examine the relationships of three variables (projected area, migration speed, and traction force) at various type I collagen surface densities in a population of fibroblasts. We observe that cell area is initially an increasing function of ligand density, but that above a certain transition level, increases in surface collagen cause cell area to decline. The threshold collagen density that ...

OBJECTIVE To investigate the causes of hypertrophy in recurrent tonsillitis with hypertrophy (RTTH). DESIGN An immunohistochemical study of recurrent tonsillitis with or without hypertrophy and adenoid tissue. SETTING Academic medical center. PATIENTS The study population comprised 15 patients with RTTH, 15 patients with recurrent tonsillitis (RT), 9 patients with adenoid vegetation, and ...

assessment and management of the environmental impacts of forest harvesting operations have become increasingly critical factors in practicing commercial forestry. this study investigated soil disturbance from a forest logging system operation on an 8-hectare mixed broadleaved stand in compartment no. 309 in gorazbon district in kheyrud educational and research forest. the objective of this stu...

abstract several root measuring methods have been developed until now but there is no single method of root measurement applicable for all situations. this study was conducted to evaluate the effects of a single trinexapac-ethyl (te) and paclobutrazol application on kentucky bluegrass root growth under three irrigation treatments. evaluating of root length density (rld), root surface area (rs) ...